The present invention relates to a tool for dispensing fluids such as two-part epoxy components. The tool employs a lever mechanism, the mechanical advantage of which can be adjusted to accommodate fluids having different viscosities.
The need for the ability to dispense materials of different viscosities arises in at least two situations. First, the same material may change viscosity significantly as a result of changes in temperature. Secondly, a user may want to use a single tool to dispense different materials having significantly different formulations, and therefore, viscosities, because application may require that such formulations be used.
The tool of the present invention includes a frame which is preferably able to hold a cartridge having two separate chambers. A pair of pistons and corresponding parallel piston rods are carried by the frame. A third pushing rod, parallel to the piston rods, is attached to the piston rods at one end. Axial forces applied to the pushing rod are transferred to the piston rods through a connecting plate. A canted nut has an aperture through which the pushing rod extends. A lever actuates the canted nut causing axial movement of the rods.
The lever of the tool is comprised of an externally threaded bolt or trigger, which threads into an internally threaded fulcrum adjacent to the canted nut. One end of the bolt contacts the canted nut as the bolt moves in a pivoting motion about the pivot axis of the fulcrum. Rotation of the bolt varies the distance between the pivot axis and the point of contact between the bolt and the canted nut.